Metal-tube press



Aug, 27, 1929. HINKEL METAL TUBE PRESS Filed March 10, 1928 PatentedAug. 27 1929.

UNITED STATES PATENT- OFFICE.

LUDWIG HINKEL, F NUREMBERG, GERMANY, ASSIGNOR'TO THE FIRM TESTA G. M.

B. 31., 0F FURTH, NEAR NUREMBERG, IBAVARIA, GERMANY.

METAL-TUBE PRESS.

Application filed March 10, 1928, Seria1'No.-260,671, and in GermanyNovember 15, 1926.

consists in employing a press ram with a projecting mandrel. The saidmandrel perforates the Work, which is then transformed into a tube bythe penetration of the ram into the hole thus formed. The stroke of thepress corresponds to the total length of the mandrel and ram, and istherefore of considerable length, and this of course means that thepress must be of large dimensions.

The ram and mandrel are actuated by hydraulic pressure, which is appliedsuddenly and sets up a uniform rate of advance of the mandrel and ram.The sudden application of the pressure produces a very great strain onthe machine, and in consequence of the resulting vibration militatesagainst the precision of the pressing process. Moreover, in the case ofhydraulic presses, their specific character renders satisfactorypressing of the material impossible.

The subject of the present application is a metal-tube press, which isof horizontal design and driven by mechanical means, and in which notonly the ram, withmandrel, but also the member accommodating the work,is adapted to be displaced. Said member undergoes displacement duringthe perforating stage, while the ram moves during the pressing stage. Inthis way the stroke of the ram is considerably shortened; in fact byabout one half, and consequently the actuation of the press, and'alsothe press itself, is substantially simplified.

If, according to this invention, the known crank drive be em loyed toactuate the ram, the advantages 0 such drive can be fully utilized forthe pressing stage. With this type of drive, the rate of advance of theram increases from zero to a certain maximum, and then diminishes againto zero. The

- pressing stage therefore commences gradually and also terminatesgradually, so that the vibrations of mass and material peculiar to thehydraulic drive,are prevented, and in addition, a satisfactorypressing-out of the material is obtained.

If the member accommodating the work is not moved, but only the ram andmandrel, the aforesaid advantages of the crank drive do not becomemanifest. In these circumstances, namely, the perforating stage occupiesapproximately the initial one third of the movement of the crank, andthe pressing stage begins with a high rate of progression of the crankdrive, which conditions are againaccompanied by sudden application ofthe pressure and the concomitant vibration of the material or masses.

The invention will be clearly understood from the following descriptionaided by the annexed drawing in which a typical example is shown and inwhich Figure 1 is a diagrammatic representation of a cross section ofthepress, while Figures 2 and 3 show the mandrel and member accommodatingthe work, in various positions.

Two horizontal sliding members 1, 2 are 'displaceably mounted in theframe of the machine. One of them houses the work carrier, press bush ormember 3 accommodating the work 4, while the other forms the ram headholding the ram 5 with mandrel 6. The work carrier 1 is provided on eachside with a stud 7 engaging in the curved slot 8 of a corresponding cam9. When the cams 9 move, the studs 7 on the carrier 1 ride in the slots8 of the cams 9, and thus set up a reciprocating movement of thecarrier 1. The ram head 2 is connected, by means of a ball joint 10,with a connecting rod 11 engaging the pin 12' of a crank disc 13. Thepress is 3, with the matrix 20, is placed in the carrier.

1, and is then charged with the solid blank 4 of the work, while the ram5 and member 3 are in the positions shown in Figure 2, in

which these two members of the press are in their extreme outwardpositions. On the driving mechanism of the press being thrown into thegear, the member 3 is first moved into its forward end position (Figure1), before the crank disc 13 and the ram 5 have begun to move. Thismovement pushes the member 3 over the mandrel 6 of the ram 5; that is tosay, the mandrel perforates the work 4. When the member 3 ceases toadvance, the movement of the crank disc 13 and ram begins. The ram 5penetrates the member 3 and forces theperforated work through theintermediate space between the mandrel 6 and the matrix 20, so that thetube is formed in known manner. This alternate movement of the member 3and ram 5 is produced by designing and arranging the driving pinions 15,16, 17 and 18, 19 accordingly.

The movement of the ram increases from zero to a maximum and thendiminishes to zero again. The pressing stage therefore begins verygradually, a condition which precludes, as far as possible, thevibrations of the masses and material, which have, hitherto seriouslyimpaired the'precision of the pressing process and the quality of theresulting tubes. In addition, a satisfactory extension of the materialis effected.

The process is naturally not restricted to pressing tubes, but is alsoapplicable to pressing bars, sections, strip, wire and the like, inwhich case the mandrel and the movement of the member 3 towards thelatter can be omitted.

What. I claim is:

1. A mechanical press for producing metal tubes, comprising ahorizontally movable ram, a crank operated driving means foroperatingsaid ram, a horizontally movable work' crrying member, andmeans for transmitting motion to said member whereby the latter willmove counter to said ram so that the work carrier will be moved onlyduring the perforating period and the ram will be moved only during thepressing action.

2. A mechanical tube press comprising in combination a horizontallymovable work carrier, a horizontally movable ram comprising apreliminary piercing portion and an extruding portion, means forimparting motion to said carrier while said piercing portion' pierceswork mounted on said carrier and means for imparting motion to said ramafter said piercing operation is complete whereby said ram will extrudesaid pierced work from said carrier.

3. A mechanical tube press comprising in combination a horizontallymovable carrier, a tubular Work carrier, having a restricted opening inone end, adapted to be mounted in said carrier, a horizontally movableram comprising a preliminary piercing portion and an extruding portion,cam operated means for imparting motion to said carrier causing saidpiercing portion of said ram to pierce work mounted in said workcarrier, and means for imparting motion to said ram after said piercingoperation is complete whelieby said ram will extrude said pierced wor Intestimony whereof I aflix my signature.

LUDWIG HINKEL.

